The present invention relates generally to agricultural implements and, more particularly, to a forward folding planter having improved maneuverability and hitch loading when in a transport configuration.
Agricultural planters generally consist of a hitch boom to which a pair of wing booms are coupled. The wing booms support a series of spaced seed units that deposit seed, fertilizer or other granular material onto a planting surface, e.g., farm field. Because of the relatively large wingspan of the wing booms, the planter frame will also include a pair of draft links. The draft links extend between the hitch boom and the wing booms, and are designed to add stability to the wing booms as the planter traverses the planting surface. In some planters, the wing booms are designed to fold forward against the hitch boom. For such forward-folding planters, the wing booms will typically be folded forward when the planter is ready for transport. That is, a planter generally has a working position in which the wing booms are fully extended away from the hitch boom and a transport position in which the wing booms are folded forward. In the transport position, the width of the planter is greatly reduced which is advantageous for exiting the planting surface and for storage of the planter. Additionally, when being shipped, the planter will be placed in its transport position.
To expedite particulate matter deposition onto the planting surface, planter manufactures are adding length to the wing booms thereby allowing more seed units to be mounted along the length of the wing booms. As a result of the increases in length of the wing booms, the outer ends of the wing booms may undesirably extend past the hitch of the towing vehicle, e.g., tractor, when the planter is in the transport position. As such, large agricultural planters are typically used with telescoping rather than fixed length hitches. More particularly, the hitch boom is coupled to a telescoping hitch that is extended as the wing booms are folded forward. The telescoping hitch therefore provides clearance for the tractor when the outer ends of the wing booms come together.
When the wing booms have been folded forward and engaged with the telescoping hitch, the telescoping hitch is lifted to provide clearance for the wheels that support the wing booms above the planting surface. This lifting of the hitch loads the rear wheels supporting the hitch boom and the hitch itself with a majority of the weight of the planter, which can result in overloading. In addition, it can be difficult to turn the planter when it is being towed as the elongation of the hitch to accommodate the folded wing booms greatly adds to the length of tow and thus the area required for cornering the planter.
When the wing booms are folded forward, the draft links connected between the hitch boom and the wing booms cause the hitch boom to pull on the telescoping hitch to effectively extend the telescoping hitch to provide the aforementioned clearance for the wing booms. As such, the lengths of the draft links and their connection points to their respective wing booms dictate how far the telescoping hitch is extended. The farther out on the wing boom the connection point the more of the telescoping hitch that will be extended when the wing booms are folded forward. Therefore, the desired change in length, dictated by the amount of room required for the tractor to clear the wing booms when the booms are in the fully folded position, dictates the position the connection point of the draft links to the wing booms. However, the amount of length required to extend the hitch often results in a connection point that is structurally insufficient to support the draft links when the wing booms are in their working position. As such, it is generally necessary to use heavy hinges to connect the draft links to the wing booms and undesirably expose the wing booms to greater stress.
Therefore, there is a need for an agricultural planter having a forward folding frame that places less load on the frame itself and the hitch when in a transport configuration. There is also a need for an agricultural planter having improved maneuverability when being transported.